Communication system, communication device, and communication method

ABSTRACT

A hands-free device  130  includes the following units: a communication unit  131  that obtains an MAC address of a portable terminal device  110  from the portable terminal device  110 ; an address storing unit  133  that registers one of MAC addresses obtained by the communication unit  131  into the address storing unit  133  itself in response to a registration trigger signal; and a control unit  136  that reads the registered MAC address from the address storing unit  133  and specifies a portable terminal device  110 , which has the read registered address, as a communication target device in response to a search trigger signal.

BACKGROUND OF THE INVENTION

[0001] (1) Field of the Invention

[0002] The present invention relates to a communication system and a communication device, such as a portable telephone and a hands-free communication device, and to a communication method thereof.

[0003] (2) Description of Related Art

[0004] The following describes a hands-free communication system as an example of a conventional communication system with reference to drawings.

[0005]FIG. 1 is a block diagram showing a conventional hands-free communication system 1000.

[0006] This hands-free communication system 1000 comprises a portable terminal device 1010 and a hands-free device 1030. The portable terminal device 1010 is a portable telephone. The hands-free device 1030 is installed in an automobile and conducts communications over a telephone network by communicating with the portable terminal device 1010 that is brought into the automobile.

[0007] The portable terminal device 1010 includes the following elements: a terminal interface unit 1011 that functions as an interface for communication via a 16-conductor cable 1020; a microphone 1014 that collects voices of a user of the portable terminal device 1010; a speaker 1015 that outputs voices of the other person to whom the user talks on the portable terminal device 1010; a display unit 1016 that displays a telephone number and the like; and a terminal control unit 1013 that controls the terminal interface unit 1011, the microphone 1014, the speaker 1015, and the display unit 1016.

[0008] When this portable terminal device 1010 is set in normal mode and communicates with another telephone via the telephone network, the terminal device 1010 has the microphone 1014, the speaker 1015, and the display unit 1016 operate under the control of the terminal control unit 1013. In this normal mode, the user holds the portable terminal device 1010 in his hand and speaks with the other person who uses another telephone.

[0009] The hands-free device 1030 includes the following elements: an interface unit 1031 that functions as an interface for communication via the 16-conductor cable 1020; a microphone 1037 affixed on a rearview mirror of the automobile, for instance, to collect voices of a driver; a speaker 1038 that outputs voices of the other person to whom the driver talks through the hands-free device 1030; a display unit 1039 that displays a telephone number and the like; a control unit 1036 that controls the interface unit 1031, the microphone 1037, the speaker 1039, and the display unit 1039; and an input unit 1040 that includes operational buttons and gives an instruction to the control unit 1036 in accordance with operations on the operational buttons.

[0010] With this hands-free communication system 1000, the 16-conductor cable 1020 connects the terminal interface unit 1011 of the portable terminal device 1010 with the interface unit 1031 of the hands-free device 1030. In this way, the portable terminal device 1010 is connected to the hands-free device 1030 in a one-to-one relationship.

[0011] As soon as the portable terminal device 1010 and the hands-free device 1030 are connected to each other in this way, the portable terminal device 1010 switches its operational mode from the normal mode to the hands-free mode so that the user can speak over the terminal device 1010 without holding it in his hand. Hereafter, such communication is called “hands-free communication”.

[0012] The following describes operation performed by the conventional hands-free communication system 1000 when the portable terminal device 1010 clears the normal mode and switches, together with the hands-free device 1030, to the hands-free mode.

[0013]FIG. 2 is a sequence diagram showing this operation of the hands-free communication system 1000.

[0014] As soon as the portable terminal device 1010 and the hands-free device 1030 are connected to each other with the 16-conductor cable 1020 (step S900), the portable terminal device 1010 clears the normal mode and switches to the hands-free mode to perform hands-free communication (step S902). At the same time, the hands-free device 1030 also switches to the hands-free mode (step S904).

[0015] Consequently, the hands-free communication system 1000 performs hands-free activation operation that activates the microphone 1037 and the speaker 1038 so that the user can perform the hands-free communication for calling another telephone or receiving a call from another telephone (step S906).

[0016] In more detail, when the portable terminal device 1010 receives a call while the terminal device 1010 and the hands-free device 1030 are set in the hands-free mode, the terminal device 1010 notifies the hands-free device 1030 of reception of the call, so that the control unit 1036 of the hands-free device 1030 has the speaker 1038 output ringing sounds. When the control unit 1036 receives an instruction to answer the telephone from the input unit 1040, the portable terminal device 1010 and the hands-free device 1030 perform the aforementioned hands-free activation operation. This enables the driver (i.e., the user) to hear voices of the other person on the line through the speaker 1038 and sends his own voices collected by the microphone 1037 to the other person so as to perform the hands-free communication.

[0017] On the other hand, when the driver operates on the input unit 1040 to request the hands-free device 1030 to make a call while the terminal device 1010 and the hands-free device 1030 are in the hands-free mode, the control unit 1036 of the hands-free device 1030 notifies the portable terminal device 1010 of this request, so that the terminal device 1010 makes the requested telephone call to other telephone. When the telephone call is answered, the hands-free device 1030 and the portable terminal device 1010 perform the hands-free activation operation. As a result, the driver can conduct the hands-free communication.

[0018] The conventional hands-free communication system 1000, however, requires the user to perform troublesome manual operation to connect the portable terminal device 1010 to the hands-free device 1030 with the 16-conductor cable 1020.

[0019] In addition, when the hands-free device 1030 and a plurality of the portable terminal devices 1010 are connected to one another with either a bus network or a wireless network with these devices 1030 and 1010 within a communicable range, then the hands-free device 1030 cannot specify, out of the plurality of portable terminal devices 1010, a portable terminal device 1010 with which it should establish a communication link.

SUMMARY OF THE INVENTION

[0020] In view of the above problems, the present invention aims to provide a communication device capable of specifying a target communication device and establishing a communication link with the specified target communication device without requiring any troublesome user operation. The present invention also aims to provide a communication system and a communication method for which such communication device is used.

[0021] To achieve the above object, the communication system of the present invention includes a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device. A different address is assigned to each communication device. One of the plurality of communication devices includes: an obtaining unit operable to obtain an address of another communication device from the another communication device; a registering unit operable to register one of addresses obtained by the obtaining unit into the registering unit in response to a reception of a first trigger signal; and a specifying unit operable to read the registered address from the registering unit and specify a communication device as a target communication device in response to a reception of a second trigger signal, the specified communication device having the read registered address.

[0022] With this construction, in response to the first trigger signal, the address of the another communication device is registered in the one of the plurality of communication devices. In response to the second trigger signal, the one of communication devices specifies, as a target communication device, a communication device whose address it registers. Consequently, the user can have the one of the communication devices specify a target communication device and establish a communication link with the specified target communication device.

[0023] The present invention may be also embodied as a communication system that includes a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device. A different address is assigned to each communication device. One of the plurality of communication devices includes: an obtaining unit operable to obtain a set of identification (ID) information assigned to a user, and an address of another communication device from the another communication device; a registering unit operable to associate an obtained address with a latest set of ID information that is most recently obtained by the obtaining unit, and register the obtained address and the latest set of ID information into the registering unit; and a specifying unit operable to search the registering unit for the latest set of ID information and specify a communication device as a target communication device, the specified communication device having the address associated with the latest set of ID information.

[0024] For this construction, an address of another communication device is associated with a latest set of ID information and registered in the one of the plurality of communication devices, which then specifies, as a target communication device, the another communication device having the address associated with the latest set of ID information. Consequently, the user can have the one of the plurality of communication devices specify a target communication device and establish a communication link with the specified target communication device. In addition, the one of the plurality of communication devices can select a different target communication device for each user because an address of a target communication device is associated with a latest set of ID information to be registered.

[0025] Here, the one of the plurality of communication devices may also include a selecting unit operable to select, in accordance with an operation by a user, one of addresses obtained by the obtaining unit, and the registering unit may register the selected address.

[0026] With this construction, the address selected by the selecting unit is registered in the one of the plurality of communication devices. This allows the user to select a desired target communication device to register by operating the selecting unit.

[0027] Here, the obtaining unit may also obtain user information from the another communication device. This user information indicates information regarding a user of the another communication device. The one of the plurality of communication devices may also include a display unit operable to display the obtained user information.

[0028] With this construction, the display unit displays information regarding users of target communication devices. This allows an operator of the display unit to know information on users of the target communication devices whose addresses have been obtained by the one of the communication devices, so that the operator can select a target communication device of a desired user to register in the one of the communication devices.

[0029] The present invention may be also embodied as communication system that includes a plurality of communication devices, each of which performs wireless communication with another communication device out of the plurality of communication devices by obtaining an address of the another communication device. A different address is assigned to each communication device. One of the plurality of communication devices includes: an obtaining unit operable to obtain an address of another communication device from the another communication device through wireless communication; a measuring unit operable to measure an electric field intensity of a wireless signal sent from the another communication device; a registering unit operable to associate the obtained address with an electric field intensity that is measured by the measuring unit when the address is obtained, and to register the address and the electric field intensity associated with each other in the registering unit; and a specifying unit operable to search the registering unit for a highest electric field intensity and specify a communication device as a target communication device, the specified communication device having an address associated with the highest electric field.

[0030] The above one of the plurality of communication devices specifies, as a target communication device, a communication device that sends a wireless signal of the highest electric field intensity. The user can therefore have the one of the plurality of communication devices specify a target communication device to establish a communication link without performing any troublesome operation. In addition, there is a high probability of the one of the communication devices specifying, as a target communication device, a communication device present nearest the one of the communication devices. Accordingly, when the above communication system is applied to a hands-free system, a hands-free device (i.e., the one of the plurality of communication devices) can select the most suitable portable terminal device (i.e., another communication device) as a target communication device.

[0031] The present invention may be also embodied as a communication system that includes a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device. A different address is assigned to each communication device. One of the plurality of communication devices includes: an obtaining unit operable to obtain an address of another communication device from the another communication device; a registering unit operable to associate the obtained address with a priority and register the address associated with the priority into the registering unit; and a specifying unit operable to specify a communication device as a target communication device, the specified communication device having an address associated with a highest priority of all priorities registered in the registering unit.

[0032] With this construction, an address of the another communication device is associated with a priority and registered in the one the plurality of communication devices, which then specifies, as its target communication device, a communication device that has a registered address associated with the highest priority. Consequently, the user can have the one of the communication devices select a target communication device to establish a communication link without performing any trouble some operation.

[0033] The present invention may be also embodied as a communication method used for a communication device to specify a target communication device and as a program to have a computer perform this communication method. Such program may be recorded on a recording medium such as a CD-ROM (compact disc read-only memory), or distributed via a transmission medium such as a communication network.

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] These and the other objects, advantages and features of the invention will become apparent from the following description thereof taken in conjunction with the accompanying drawings which illustrate a specific embodiment of the invention.

[0035] In the drawings:

[0036]FIG. 1 is a block diagram showing a conventional hands-free communication system;

[0037]FIG. 2 is a sequence diagram showing operation of the conventional hands-free communication system;

[0038]FIG. 3 is an external view of a hands-free communication system or the first embodiment according to the present invention;

[0039]FIG. 4 is a block diagram showing the hands-free communication system of FIG. 3;

[0040]FIG. 5 is a sequence diagram showing registration operation performed by the hands-free communication system;

[0041]FIG. 6 shows a registration screen used for the first embodiment;

[0042]FIG. 7 is a table showing address data used for the first embodiment;

[0043]FIG. 8 is a sequence diagram showing operation performed by hands-free communication system to specify a portable terminal device;

[0044]FIG. 9 is a sequence diagram showing registration operation performed by the hands-free communication system;

[0045]FIG. 10 shows another registration screen used for the first embodiment;

[0046]FIG. 11 is a sequence diagram showing operation by the hands-free communication system to specify a portable terminal device;

[0047]FIG. 12 is an external view of a hands-free communication system of the second embodiment according to the present invention;

[0048]FIG. 13 is a block diagram showing the hands-free communication system of FIG. 12;

[0049]FIG. 14 is a table showing example contents of information stored in a storing unit of a portable terminal device for the second embodiment;

[0050]FIG. 15 is a sequence diagram showing registration operation by the hands-free communication system;

[0051]FIG. 16 shows a registration screen used for the second embodiment;

[0052]FIG. 17 is a front view of a part of an operating unit that includes a move button, an “ENTER” button, and a “CANCEL” button;

[0053]FIG. 18 is a table showing personal registration data for the second embodiment;

[0054]FIG. 19 is a sequence diagram showing operation performed by the hands-free communication system to specify a portable terminal device;

[0055]FIG. 20 shows a configuration of the hands-free communication system, for which three portable terminal devices are registered in a hands-free device for the second embodiment;

[0056] FIGS. 21A˜21C are tables showing contents of information stored in a storing unit of each portable terminal device;

[0057]FIG. 22 shows another registration screen used for the second embodiment;

[0058]FIG. 23 is a table showing personal registration data for the second embodiment;

[0059]FIG. 24 shows another registration screen displayed for the second embodiment;

[0060]FIG. 25 is a table showing the personal registration data that has been updated;

[0061]FIG. 26 is a sequence diagram showing operation performed by the hands-free communication system to specify a portable terminal device;

[0062]FIG. 27 shows a configuration of the hands-free communication system in which three portable terminal devices exist within the communicable ranges of three hands-free devices;

[0063] FIGS. 28A˜28C are tables showing personal registration data stored in the three hands-free devices;

[0064]FIG. 29 shows a hands-free system that includes a portable terminal device having a function of the hands-free device;

[0065]FIG. 30 is a table showing personal registration data that includes priorities for the second embodiment;

[0066]FIG. 31 is a block diagram showing a hands-free communication system of the third embodiment according to the present invention;

[0067]FIG. 32 is a block diagram showing a hands-free communication system of the fourth embodiment;

[0068]FIG. 33 shows a configuration of the hands-free communication system including three portable terminal devices within a communicable range of a hands-free device;

[0069]FIG. 34 is a sequence diagram showing operation performed by the hands-free communication system to specify a portable terminal device; and

[0070]FIG. 35 is a table showing field intensity data for the fourth embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0071] The following specifically describes the present invention based on several embodiments with reference to drawings.

[0072] First Embodiment

[0073] The following describes a hands-free communication system of the first embodiment of the present invention.

[0074]FIG. 3 is an external view of the hand-free communication system of the first embodiment.

[0075] This hands-free communication system comprises a portable terminal device 110 and a hands-free device 130. The portable terminal device 110 has functions of a portable telephone, and the hands-free device 130 is installed in an automobile and conducts communications over a telephone network by communicating with the portable terminal device 110 that is brought into the automobile.

[0076] The hands-free device 130 includes the following elements: a microphone 137 affixed on a rearview mirror, for instance, to collect voices of a driver; a speaker 138 that outputs voices of the other person with whom the driver talks through the hands-free device 130; and an instrument panel 141 that communicates with the portable terminal device 110 via a wireless communication medium 120 and controls the microphone 137 and the speaker 138 in accordance with the communication result. This instrument panel 141 is built in a front panel, a console box or the like, and connected to the microphone 137 and the speaker 138 with a connection cable 121. This connection cable 121 may be replaced with an in-vehicle bus, or a wireless medium.

[0077] The hands-free device 130 and the portable terminal device 110 communicate with each other via the wireless communication medium 120 in accordance with the communication standard of Bluetooth (a trademark of The Bluetooth SIG, Inc.). That is to say, the hands-free device 130 and the portable terminal device 110 comply with the Bluetooth standard, and communicate with each other through short-distance communications of, for instance, 10 or lower meters by using a 2.4-GHz electromagnetic wave in Industrial Scientific and Medical (ISM) frequency band.

[0078]FIG. 4 is a block diagram showing the above hands-free communication system 100.

[0079] The portable terminal device 110 includes the following elements: a terminal communication unit 111 that functions as an interface for communication via the wireless communication medium 120; a microphone 113 that collects voices of a user; a speaker 114 that outputs voices of the other person on the line; a display unit 115 for displaying a telephone number and the like; a terminal control unit 112 that controls the terminal communication unit 111, the microphone 113, the speaker 114, and the display unit 115; and a storing unit 116 that stores a Media Access Control (MAC) address and user information.

[0080] An MAC address is assigned to each device that conducts communication complying with Bluetooth, and identifies the device. The storing unit 116 stores the MAC address that is assigned to the portable terminal device 110. The user information is information on the user of the portable terminal device 110, such as a telephone number of the terminal device 110.

[0081] When this portable terminal device 110 is set in normal mode and communicates with another telephone via the telephone network, the terminal device 110 has the microphone 113, the speaker 114, and the display unit 115 operate under the control of the terminal control unit 112. In the normal mode, the user holds the portable terminal device 110 in his hand and speaks with the other person who uses another telephone.

[0082] The instrument panel 141 in the hands-free device 130 includes a communication unit 131, a display unit 139, a storing unit 132, an address storing unit 133, a control unit 136, an input unit 140, a registration trigger receiving unit 134, and a search trigger receiving unit 135. The communication unit 131 functions as an interface for communication via the wireless communication medium 120. The display unit 139 displays a telephone number and the like. The storing unit 132 stores an MAC address assigned to the hands-free device 130 for conducting communication complying with Bluetooth. The address storing unit 133 stores MAC addresses assigned to other devices that conducts Bluetooth communication. The control unit 136 controls at least the microphone 137, the speaker 138, the display unit 139, the storing unit 132, and the address storing unit 133. The input unit 140 includes operational buttons and the like, and gives an instruction to the control unit 136 in accordance with operation on these buttons. The registration trigger receiving unit 134 and the search trigger receiving unit 135 receive a registration trigger signal and a search trigger signal, respectively, from the peripheral units, and give an instruction to the control unit 136 in accordance with the received trigger signal.

[0083] This instrument panel 141 may also have additional functions, such as for displaying an operational state of other in-vehicle apparatuses including an air conditioner and a car audio unit and for functioning as an interface for such display. The instrument panel 141 may also have functions as an automobile navigation system, a car audio unit, a television, and the like.

[0084] The speaker 138 may be shared by other units within the hands-free communication system 100, the car audio unit, and/or the automobile navigation system. In such case, the speaker 138 outputs not only voices of the other person on the line but also music and sound sent from the car audio unit, and guiding voices sent from the automobile navigation system.

[0085] The hands-free device 130 exchanges MAC addresses with another device complying with Bluetooth communication, and registers the MAC address of the other device into the address storing unit 133 in accordance with the registration trigger signal. When receiving the search trigger signal, the hands-free device 130 specifies a device whose address is registered in the address storing unit 133, and establishes a communication link with the specified device.

[0086] With reference to FIG. 5, the following sequentially describes operation performed by the hands-free device 130 to register the MAC address of the portable terminal device 110 when the terminal device 110 is brought into the automobile equipped with the hands-free device 130.

[0087]FIG. 5 is a sequence diagram showing this operation of the hands-free communication system 100.

[0088] The control unit 136 of the hands-free device 130 always searches for a device with which the device 130 can conduct Bluetooth communication in accordance with a result of communication by the communication unit 131 via the wireless communication medium 120.

[0089] When the user brings the portable terminal device 110 into the automobile, and the terminal device 110 enters a communicable range of the hands-free device 130, the control unit 136 of the hands-free device 130 recognizes the device 110 through the above search as a device with which it can communicate (step S100). The control unit 136 then has the communication unit 131 send a request signal requesting the portable terminal device 110 to send its MAC address and user information.

[0090] Responding to this request signal, the terminal control unit 112 of the potable terminal device 110 has the terminal communication unit 111 send the MAC address and user information stored in the storing unit 116 to the hands-free device 130. The control unit 136 of the device 130 then receives them via the communication unit 131, and temporarily stores them into the storing unit 132 (step S102). That is to say, the control unit 136 and the communication unit 131 of the hands-free device 130 function as a means for obtaining the MAC address and user information.

[0091] The control unit 136 then has the communication unit 131 send the MAC address of the hands-free device 130 stored in the storing unit 132 to the portable terminal device 110.

[0092] The terminal control unit 112 receives this MAC address via the terminal communication unit 111, and temporarily stores it into the storing unit 116 (step S104).

[0093] In this way, the portable terminal device 110 and the hands-free device 130 exchange their MAC addresses, so that they can specify and communicate with each other.

[0094] When the registration trigger signal is inputted from the peripheral unit to the hands-free device 130 (step S106) and detected by the registration trigger receiving unit 134 (step S108), the trigger receiving unit 134 instructs the control unit 136 to register the MAC address of the portable terminal device 110 currently stored in the storing unit 132.

[0095] On receiving this instruction, the control unit 136 reads the MAC address of the portable device 110 from the storing unit 132 via the communication unit 131, and registers the read MAC address into the address storing unit 133 (step S110). That is to say, the address storing unit 133 and the control unit 136 function as a means for registering an MAC address.

[0096] The above registration trigger signal is outputted from the peripheral unit when the user presses an operational button on the front of the instrument panel 141.

[0097] The control unit 136 also reads the MAC address and user information from the storing unit 132 via the communication unit 131, and has the display unit 139 display the read MAC address and user information. By referring to the displayed user information, the user recognizes that the portable terminal device 110 can currently communicate with the hands-free device 130. When the user wishes to conduct hands-free communication, such as during driving, by having the hands-free device 130 communicate with the portable terminal device 110, the user presses the above operational button to have the registration trigger signal outputted.

[0098] It is alternatively possible to provide a touch panel function to the display unit 139 and embody the above operational button on the display unit 139. In this case, the display unit 139 outputs the registration trigger signal to the registration trigger receiving unit 134 in accordance with a touch operation by the user.

[0099]FIG. 6 shows a registration screen presented by the display unit 139 to prompt the user to register a device with which a communication link should be established.

[0100] This registration screen includes a user information area 1 w, a registration button 2 b, and a cancel button 3 b. In the user information area 1 w, the user information for the device that can be registered as a communication link destination is displayed. On receiving a touch by the user, the registration button 2 b has the display unit 139 output the registration trigger signal to register the device specified by the displayed user information as a communication link destination. On receiving a touch by the user, the cancel button 3 b has the display unit 139 output a cancel signal to cancel the above registration.

[0101] For example, as shown in FIG. 6, user information “090-1234-5678” of the portable terminal device 110 is displayed in the user information area 1 w. From this user information, that is, a telephone number, the user judges that the portable terminal device 110 can communicate with the hands-free device 130. When the user wishes to conduct the hands-free communication, such as during driving, by having the hands-free device 130 communicate with the portable terminal device 110, he touches the registration button 2 b, so that the display unit 139 outputs the registration trigger signal.

[0102] The registration trigger receiving unit 134 detects this registration trigger signal, and instructs the control unit 136 to register the MAC address stored in the storing unit 132 as described above. The control unit 136 then associates this MAC address with the user information to produce address data 133 a, and registers the produced address data 133 a in the address storing unit 133.

[0103]FIG. 7 is a table showing the address data 133 a.

[0104] This address data 133 a includes the MAC address “0x1234567890AB” and the user information “090-1234-5678”.

[0105] With the above registration screen, when the user touches the cancel button 3 b and the display unit 139 outputs the cancel signal to the control unit 136, the control unit 136 instructs the display unit 139 to clear the registration screen.

[0106] In the above example, the telephone number is displayed as the user information in the user information area 1 w. However, it is alternatively possible to display, as the user information, a name of an owner of a device complying with the Bluetooth standard, or an MAC address of such device.

[0107] In this way, the hands-free device 130 registers the portable terminal device 110 as a communication link destination in accordance with a user operation on either the operational button or the registration button 2 b of the display unit 138.

[0108] With reference to FIG. 8, the following sequentially describes operation performed by the hands-free communication system 100 to conduct hands-free activation operation when the portable terminal device 110, which has been registered in the stated manner, is brought into the automobile.

[0109]FIG. 8 is a sequence diagram showing this operation of the hands-free communication system 100.

[0110] As in steps S100˜S104 shown in FIG. 5, the user brings the portable terminal device 110 into the automobile, so that the terminal device 110 enters the communicable range of the hands-free device 130. The hands-free device 130 then obtains the MAC address and the user information of the portable terminal device 110, and the terminal device 110 obtains the MAC address of the hands-free device 130.

[0111] When the hands-free device 130 receives the search trigger signal at this point from the peripheral unit (step S200), the search trigger receiving unit 135 of the device 130 detects this trigger signal (step S202).

[0112] This search trigger signal is outputted by a search trigger transmitting unit 135 a when the engine of the automobile is turned on. More specifically, when the user inserts a car key into a keyhole on the side of a steering wheel and turns the key in the direction to start the engine, the search trigger transmitting unit 135 a detects this turn of the key, and outputs the search trigger signal.

[0113] After detecting such search trigger signal, the search trigger receiving unit 135 notifies the control unit 136 of the detection, so that the control unit 136 searches the address data 133 a in the address storing unit 133 for a registered MAC address (step S204).

[0114] As a result of the search, the control unit 136 finds the MAC address “0x1234567890AB”, specifies the portable terminal device 110 having the found MAC address as a communication target device. The control unit 136 then establishes Bluetooth communication link between the communication unit 131 of the hands-free device 130 and the terminal communication unit 111 of the portable terminal device 110 (step S206). In this way, the control unit 136 functions as a means for specifying a communication target device.

[0115] When the address data 133 a in the address storing unit 133 does not include any MAC address, and therefore the control unit 136 does not find any MAC address in step S204, then the control unit 136 does not establish the communication link. Consequently, the portable terminal device 110 in the automobile conducts communication in the normal mode.

[0116] When the communication link is established as stated above, the hands-free device 130 and the portable terminal device 110 switch to hands-free mode to enable the hands-free activation operation that is described later.

[0117] More specifically, the control unit 136 requests, via the communication unit 131, the portable terminal device 110 to switch to the hands-free mode (step S208).

[0118] The terminal control unit 112 of the portable terminal device 110 receives this request via the terminal communication unit 111, and notifies the hands-free device 130 that the terminal device 110 is going to switch to the hands-free mode (step S210).

[0119] Following this, both the portable terminal device 110 and the hands-free device 130 switch to the hands-free mode (steps S212 and S214). The hands-free communication system 100 then performs the aforementioned hands-free activation operation, which is an operation to activate the microphone 137 and the speaker 138, so that the hands-free communication can be conducted when the user calls another telephone by using the hands-free device 130, or when the portable terminal device 110 receives a call from another telephone (step S216).

[0120] As has been described, communication target devices for the hands-free device 130 are registered in the device 130 in advance. When the user carrying one of the registered devices, that is, the portable terminal device 110 starts the engine of the automobile, the hands-free device 130 automatically specifies the portable terminal device 110 as a communication target device without requiring the user to perform cable connection as in the conventional system, and establishes the communication link with the terminal device 110.

[0121] The operation of the hands-free communication system 100 has been described based on examples in which a single portable terminal device 110 complying with the Bluetooth standard is brought into the automobile. The following describes examples in which a plurality of such portable terminal devices 110 are brought into the automobile.

[0122]FIG. 9 is a sequence diagram showing operation of the hands-free communication system 100 to register MAC addresses of first and second portable terminal devices 110.

[0123] Through communication by the communication unit 131 via the wireless communication medium 120, the control unit 136 of the hands-free device 130 always searches for a device with which the device 130 can conduct Bluetooth communication.

[0124] When the driver and a passenger bring the first and second portable terminal devices 110, respectively, into the automobile, and therefore these terminal devices 110 enter into a communicable range of the hands-free device 130, the control unit 136 of the device 130 recognizes the first and second portable terminal devices 110 through the above search as devices with which it can perform Bluetooth communication (step S300). The control unit 136 then has the communication unit 131 send a request signal that requests the first and second portable terminal devices 110 to send their MAC addresses and user information.

[0125] Responding to this request signal, the first and second portable terminal devices 110 send their MAC addresses and user information stored in their respective storing units 116 to the hands-free device 130. The control unit 136 of the hands-free device 130 receives them via the communication unit 131, associates each MAC address with user information, and temporarily stores them into the storing unit 132 (step S302). The control unit 136 then instructs the communication unit 131 to send the MAC address of the hands-free device 130 stored in the storing unit 132.

[0126] The first and second portable terminal devices 110 receive this MAC address via the terminal communication unit 111, and temporarily stores it into the storing unit 116 (steps S304 and S306).

[0127] In this way, the first and second portable terminal devices 110 and the hands-free device 130 exchange their MAC addresses, so that the hands-free device 130 can specify one of the first and second portable terminal devices 110 as a communication target device and establish a communication link with the specified potable terminal device 110.

[0128] When receiving a plurality of MAC addresses and sets of user information as described above, the control unit 136 of the hands-free device 130 displays a registration screen that prompts the user to register a device with which the communication link should be established. When the display unit 139 has a touch panel function, the display unit 139 displays not only user information of the first and second portable terminal devices 110 on the registration screen but also a selecting means for allowing the user to select, through a touch operation, one of the portable terminal devices 110 to register as a communication link destination (step S308).

[0129]FIG. 10 shows this registration screen displayed by the display unit 139.

[0130] The registration screen includes two user information areas 1 w, a registration button 2 b, a cancel button 3 b, and a triangular mark 1 y that indicates one of the user information areas 1 w. In one user information area 1 w, the telephone number “090-1234-5678”, that is, the user information of the first potable terminal device 110 is displayed. In the other user information area 1 w, a telephone number “090-5678-1234”, that is, user information of the second portable terminal device 110 is displayed. This registration screen also includes move buttons 4 b and 5 b to move the triangular mark 1 y.

[0131] When the user wishes to register the second portable terminal device 110 as a communication link destination, the user touches the move buttons 4 b and 5 b to have the triangular mark 1 y indicate the telephone number “090-5678-1234” of the second portable terminal device 110, and then touches the registration button 2 b.

[0132] Consequently, the display unit 139 outputs the registration trigger signal to register the second portable terminal device 110 as a communication link destination (step S310).

[0133] The registration trigger receiving unit 134 detects the above registration trigger signal (step S312), and instructs the control unit 136 to register the MAC address that is stored in the storing unit 132 and associated with the telephone number “090-5678-1234”.

[0134] On receiving this instruction, the control unit 136 obtains this MAC address and the associated user information from the storing unit 132 via the communication unit 131, and registers them into the address storing unit 133 (step S314).

[0135] In this way, the user operates on the registration button 2 b and the move buttons 4 b and 5 b to register the second portable terminal device 110 into the hands-free device 130 as a communication link destination.

[0136] With reference to FIG. 11, the following sequentially describes operation that ends with the hands-free activation operation performed by the registered second portable terminal device 110 and the hands-free device 130 when the first and second portable terminal devices 110 are brought into the automobile.

[0137]FIG. 11 is a sequence diagram showing this operation of the hands-free communication system 100.

[0138] When the users bring the first and second portable terminal devices 110 into the automobile, both the terminal devices 110 enter the communicable range of the hands-free device 130. As in steps S300˜S306 shown in FIG. 9, the hands-free device 130 obtains MAC addresses and user information of the first and second portable terminal devices 110, which in turn obtain the MAC address of the hands-free device 130.

[0139] When the hands-free device 130 receives the search trigger signal at this point from the peripheral unit (step S400), the search trigger receiving unit 135 detects this trigger signal (step S402).

[0140] This search trigger signal is outputted by the search trigger transmitting unit 135 a as in step S200 in FIG. 8.

[0141] On detecting the search trigger signal, the search trigger receiving unit 135 notifies the control unit 136 of the detection, so that the control unit 136 searches for an MAC address in the address data 133 a registered in the address storing unit 133 (step S404).

[0142] As a result of the search, the control unit 136 finds the MAC address of the second portable terminal device 110, and specifies the second portable terminal device 110 as a communication target device. The control unit 136 then establishes Bluetooth communication link between the communication unit 131 of the hands-free device 130 and the terminal communication unit 111 of the second portable terminal device 110 (step S406).

[0143] When the address data 133 a in the address storing unit 133 does not include any MAC address, and therefore the control unit 136 does not find any MAC address in step S404, then the control unit 136 does not establish the communication link. When the communication link is established, the hands-free device 130 and the portable terminal device 110 switch to the hands-free mode to enable the hands-free activation operation.

[0144] More specifically, the control unit 136 requests, via the communication unit 131, the second portable terminal device 110 to switch to the hands-free mode (step S408).

[0145] The terminal control unit 112 of the second portable terminal device 110 receives this request via the terminal communication unit 111, and notifies the hands-free device 130 that the terminal device 110 is going to switch to the hands-free mode (step S410).

[0146] Following this, both the second portable terminal device 110 and the hands-free device 130 switch to the hands-free mode (steps S412 and S414).

[0147] Consequently, the second portable terminal device 110 and the hands-free device 130 perform the hands-free activation operation by activating the microphone 137 and the speaker 138, so that the hands-free communication can be conducted when the user calls another telephone by using the hands-free device 130, or when the second portable terminal device 110 receives a call from another telephone (step S416).

[0148] As has been described, a portable terminal device 110 desired by the user as a communication link destination of the hands-free device 130 is registered in the device 130 in advance. With this technique, the hands-free device 130 can automatically specify the registered portable terminal device 110 as a communication target device as soon as the user starts the engine even when the user brings a plurality of portable terminal devices 110 into the automobile. As a result, Bluetooth communication link is established between the hands-free device 130 and the specified portable terminal device 110.

[0149] For the above embodiment, the registration trigger signal is outputted in accordance with operation on the registration button 2 b displayed on the touch panel achieved by the display unit 139. It is alternatively possible, however, to have the control unit 136 of the hands-free device 136 monitor a communication state of the portable terminal device 110 sending the MAC address and user information by referring to a signal sent from the portable terminal device 110 to the communication unit 131. In this case, the control unit 136 outputs the registration trigger signal when the monitored communication state satisfies a predetermined communication condition. This may be performed, for instance, by having the control unit 136 measure electric field intensity of a wireless signal sent from the portable terminal device 110 and having the registration trigger signal outputted when the measured electric field intensity is higher than a predetermined value. In this case, an MAC address of a portable terminal device 110 can be automatically registered in the address storing unit 133 without user operation.

[0150] It is also possible to associate the above communication state with the MAC address and user information of the portable terminal device 110 and to temporarily store them into the storing unit 132 as a set of information. When the total number of such sets of information in the storing unit 132 reaches a predetermined number, the control unit 136 may specify a portable terminal device 110 associated with the best communication state (e.g., the highest electric field intensity) of all the stored communication states, and have the registration trigger signal outputted so as to register the specified portable terminal device 110. In this case, too, an MAC address of the portable terminal device 110 can be automatically registered in the address storing unit 133 without user operations. In addition, the hands-free device 130 can specify a portable terminal device 110 in the best communication state as a communication target device.

[0151] It is alternatively possible to assign a priority to each pair of an MAC address and user information obtained from a portable terminal device 110 and to temporarily store them in the storing unit 132. When the registration trigger signal is outputted while a plurality of pairs are stored in the storing unit 132, the control unit 136 registers an MAC address, which is included in a pair with the highest priority, into the address storing unit 133.

[0152] The above embodiment states that the search trigger transmitting unit 135 a outputs a search trigger signal when the engine is started. The search trigger signal, however, may be alternatively outputted by a sensor that is affixed on a driver's seat to detect a movement of the driver taking the seat. This allows the hands-free device 130 to specify an appropriate portable terminal device 110 as a communication target device and establish a communication link with it as soon as the driver simply takes the seat.

[0153] It is alternatively possible to provide the search trigger transmitting unit 135 a in a transmitter of a keyless entry system.

[0154] This transmitter is integrated with a car key. When the user operates on an operational button on the transmitter, the transmitter transmits an unlock signal to unlock car doors. The search trigger transmitting unit 135 a in this transmitter detects the user operation on the above operational button, and outputs the search trigger signal at almost the same time as the output of the unlock signal.

[0155] As a result, the hands-free device 130 can specify an appropriate portable terminal device 110 as a communication target device and establish a communication link with it as soon as the driver simply operates the transmitter to unlock the car door.

[0156] Second Embodiment

[0157] The following describes a hands-free communication system of the second embodiment of the present invention.

[0158]FIG. 12 is an external view of the hand-free communication system of the second embodiment.

[0159] The present hands-free communication system has a characteristic in that a personal ID (identifier) is registered into a hands-free device 230, and comprises the following elements: a portable terminal device 210 that has a function of a portable telephone; the hands-free device 210 installed in an automobile and conducts communication over a telephone network by communicating with the portable terminal device 210 brought in the automobile; and a personal ID device 260 that stores a personal ID identifying each user and outputs it in accordance with operation of the user.

[0160] The personal ID device 260 is integrated into a car key, and also functions as a transmitter of a keyless entry system. When the user operates on an operational button of the personal ID device 260, the personal ID device 260 transmits the stored personal ID and an unlock signal to unlock car doors. Such personal ID device 260 is provided to each user.

[0161] The personal ID device 260 may be achieved by a fingerprint authentication device that outputs a fingerprint of the user as his ID information, or by a password input device that stores a password in advance and outputs it in response to user operation.

[0162] As in the first embodiment, the hands-free device 230 includes the following elements: a microphone 237 that is affixed on a rearview mirror, for instance, in the automobile to collect voices of a driver; a speaker 238 that outputs voices sent from the other person with whom the driver talks through the hands-free device 230; and an instrument panel 241 that communicates with the portable terminal device 210 via a wireless communication medium 220 and that controls the microphone 237 and the speaker 138 in accordance with the communication result. This instrument panel 241 is built into a front panel, a console box, or the like in the automobile. The microphone 237 and the speaker 238 are connected to the instrument panel 241 with a connection cable 221.

[0163] The hands-free device 230 and the portable terminal device 210 communicate with each other via the wireless communication medium 220 in accordance with the communication standard of Bluetooth.

[0164]FIG. 13 is a block diagram showing the above hands-free communication system 200.

[0165] The portable terminal device 210 has basically the same construction as the portable terminal device 110 of the first embodiment, and includes the following elements: a terminal communication unit 211 that functions as an interface for communication via the wireless communication medium 220; a microphone 213 that collects voices of a user; a speaker 214 that outputs voices of the other person on the line; a display unit 215 that displays a telephone number and the like; a terminal control unit 212 that controls the terminal communication unit 211, the microphone 213, the speaker 214, and the display unit 215; and a storing unit 216 that is achieved by RAM, for example, and stores an MAC address and user information assigned to the portable terminal device 210.

[0166]FIG. 14 shows an example table stored in the storing unit 216.

[0167] The storing unit 216 shown in this figure stores an MAC address “0x1234567890AB” and user information “090-1234-5678” associated with this MAC address.

[0168] When this portable terminal device 210 is set in normal mode and communicates with another telephone via the telephone network, the terminal device 110 has the microphone 213, the speaker 214, and the display unit 215 operate under the control of the terminal control unit 212. In the normal mode, the user holds the portable terminal device 210 in his hand and speaks with the other person who uses another telephone.

[0169] The instrument panel 241 in the hands-free device 230 includes a communication unit 231, a display unit 239, a storing unit 232, a control unit 236, and an operating unit 233. The communication unit 231 functions as an interface for communication via the wireless communication medium 220. The display unit 239 includes, for instance, a liquid-crystal display (LCD), and displays a telephone number and the like. The storing unit 232 stores an MAC address assigned to the hands-free device 230 for Bluetooth communication. The control unit 136 controls at least the microphone 237, the speaker 238, the display unit 239, and the storing unit 232. The operating unit 233 includes operational buttons and the like to give an instruction to the control unit 236 in accordance with user operation on these buttons.

[0170] In more detail, the control unit 236 contains, for instance, the following elements: a central processing unit (CPU) that executes a program for communicating with the portable terminal device 210; read-only memory (ROM) that stores the above program; and random-access memory (RAM) that is used by the CPU as storage regions while executing the program.

[0171] The storing unit 232 is achieved by RAM, for example. Alternatively, this storing unit 232 may be achieved by the RAM in the control unit 236.

[0172] The hands-free device 230 exchanges MAC addresses with another device complying with Bluetooth communication, and registers the obtained MAC address of the other device into the storing unit 233. The hands-free device 230 specifies the device, whose MAC address is registered, as a communication target device, and establishes a communication link with the specified device.

[0173] With reference to FIG. 15, the following sequentially describes operation performed by the hands-free device 230 to register the MAC address of the portable terminal device 210 when the driver brings the above personal ID device 260 and the portable terminal device 210 into an automobile equipped with the hands-free device 230.

[0174]FIG. 15 is a sequence diagram showing this operation of the hands-free communication system 200.

[0175] The driver operates on an operational button on the personal ID device 260 to get into the automobile. The personal ID device 260 then transmits the unlock signal and the stored personal ID “1” (step S500).

[0176] The control unit 236 of the hands-free device 230 receives this personal ID, recognizes it as the latest, i.e., currently valid (step S502), and places it into the storing unit 232 (step S504).

[0177] Through communication via the wireless communication medium 220 by the communication unit 231, the control unit 236 always searches for a device with which it can conduct Bluetooth communication.

[0178] When the user has the unlock signal unlock the car doors, and gets into the automobile, carrying the portable terminal device 210, the terminal device 210 enters a communicable range of the hands-free device 230. The control unit 236 of the hands-free device 230 then recognizes the portable terminal device 210 through the above search as a device with which it can communicate (step S506), and has the communication unit 231 send a request signal to request the terminal device 210 to send its MAC address and user information.

[0179] Responding to this request signal, the terminal control unit 212 of the potable terminal device 210 has the terminal communication unit 211 send its MAC address and user information stored in the storing unit 216 to the hands-free device 230. The control unit 236 of the hands-free device 230 then receives them via the communication unit 231, and temporarily stores them into the storing unit 232 (step S508). That is to say, the control unit 236 and the communication unit 231 of the hands-free device 230 make up a means for obtaining the MAC address and user information.

[0180] The control unit 236 then has the communication unit 231 send the MAC address of the hands-free device 230 stored in the storing unit 232 to the portable terminal device 210.

[0181] The terminal control unit 212 receives this MAC address via the terminal communication unit 211, and temporarily places it into the storing unit 216 (step S510).

[0182] In this way, the portable terminal device 210 and the hands-free device 230 exchange their MAC addresses, so that they can specify each other as a communication target device.

[0183] When the user presses one of the operational buttons of the operating unit 233 of the hands-free device 230 to display a registration screen (step S512), the operating unit 233 outputs a signal. In accordance with this signal, the control unit 236 has the display unit 239 display the registration screen (step S514). This registration screen is displayed to prompt the user to register a target communication device, that is, a communication link destination for the hands-free device 230.

[0184]FIG. 16 shows an example registration screen 239 d displayed by display unit 239.

[0185] On the registration screen 239 d, “ID1” indicating the personal ID stored in the storing unit 232 is displayed next to “090-1234-5678” indicating the user information stored in the storing unit 232.

[0186] The displayed personal ID and user information have been read by the control unit 236 from the storing unit 232 in accordance with the signal from the operating unit 233. On the registration screen 239 d, a triangular candidate mark 239 m is displayed on the right of the user information. The candidate mark 239 m indicates user information of a candidate device to be registered.

[0187] While viewing the registration screen 239 d, the user operates on an “ENTER” button 233 b, and, if necessary, a move button 233 a and a “CANCEL” button 233 c (see FIG. 17) included in the operational buttons of the operating unit 233 to register the displayed communication target device of the hands-free device 230.

[0188]FIG. 17 is a front view of a part of the operating unit 233 which includes a move button 233 a, the “ENTER” button 233 b, and the “CANCEL” button 233 c.

[0189] The move button 233 a is pressed to move the candidate mark 239 m and change user information indicated by the candidate mark 239 m. The “ENTER” button 233 b is pressed to have the operating unit 233 output a registration signal to register the user information indicated by the candidate mark 239 m to the control unit 236. The “CANCEL” button 233 c is pressed to have the operating unit 233 output a cancel signal to clear the registration screen 239 d to the control unit 236. When the registration screen 239 d includes a single set of user information as shown in FIG. 16, pressing the move button 233 a does not move the candidate mark 239 m, which remains to indicate the same user information. It is alternatively possible to provide a touch panel function to the display unit 239 to make it function as the operating unit 233 as described in the first embodiment. In this case, the display unit 239 displays the move button 233 a, the “ENTER” button 233 b, and the “CANCEL” button 233 c on the registration screen 239 d.

[0190] When the user presses the “ENTER” button 233 b, the operating unit 233 outputs a registration signal to instruct registration to the control unit 236 (step S516). This registration signal corresponds to the registration trigger signal described in the first embodiment.

[0191] On receiving the registration signal, the control unit 236 associates the personal ID in the storing unit 232, and the MAC address and user information obtained in step S510 with one another to produce personal registration data 232 d, and registers the produced personal registration data 232 d in the storing unit 232. That is to say, the control unit 236 and the storing unit 232 make up a means for registering an address of the portable terminal device 210.

[0192]FIG. 18 is a table showing the personal registration data 232 d.

[0193] In this personal registration data 232 d, the personal ID “1”, the MAC address “0x1234567890AB”, and the user information “090-1234-5678” are associated with one another.

[0194] In this way, the portable terminal device 210 with the user information “090-1234-5678” is registered in the hands-free device 230 as a communication link destination of the device 230 (step S518).

[0195] With reference to FIG. 19, the following sequentially describes operation that ends with the hands-free activation operation performed by the registered portable terminal device 210 and the hands-free device 230 when the driver brings the portable terminal device 210 into the automobile.

[0196]FIG. 19 is a sequence diagram showing this operation of the hands-free communication system 200.

[0197] As described for FIG. 15, the driver operates on an operational button on the personal ID device 260 to get into the automobile. The personal ID device 260 then transmits the stored personal ID “1” and the unlock signal (step S600).

[0198] The control unit 236 of the hands-free device 230 receives this personal ID, recognizes it as currently valid (step S602), and places it into the storing unit 232 (step S604). Here, when the received personal ID is already registered in the personal registration data 232 d in the storing unit 232, the control unit 236 may register a flag indicating this personal ID as valid into the personal registration data 232 d (see FIG. 28).

[0199] When the user unlocks the car doors and gets into the automobile while carrying the portable terminal device 210, the terminal device 210 enters the communicable range of the hands-free device 230. The control unit 236 of the hands-free device 230 then recognizes the portable terminal device 210 as a device with which it can communicate (step S606).

[0200] Consequently, the hands-free device 230 sends its MAC address to the portable terminal device 210, and the terminal device 210 sends its MAC address and user information to the hands-free device 230 (steps S608 and S610).

[0201] When the control unit 236 of the hands-free device 230 receives, at this point, a connect command signal to establish a communication link (step S612), the control unit 236 searches the personal registration data 232 d in the storing unit 232 for a currently valid personal ID, that is, the personal ID “1” (step S614).

[0202] This connect command signal is outputted when the hands-free device 230 and the portable terminal device 210 are required to conduct the hands-free activation operation. For instance, the connect command signal is outputted by the operating unit 233 of the hands-free device 230 when the user operates on its operational button instructing the output of the signal. Alternatively, the connect command signal may be outputted when the engine is started as in the first embodiment.

[0203] After finding the personal ID “1” in the personal registration data 232 d, the control unit 236 reads the MAC address “0x234567890AB” associated with the found personal ID “1”, and specifies, as a communication target device, a device (i.e., the portable terminal device 210) that has the read address. The control unit 236 then establishes Bluetooth communication link between the communication unit 231 of the hands-free device 230 and the terminal communication unit 211 of the portable terminal device 210 (step S616). In this way, the control unit 236 functions as a means for specifying a communication target device for the hands-free device 230.

[0204] When the communication link is established, the hands-free device 230 and the portable terminal device 210 switch to the hands-free mode to enable the hands-free activation operation.

[0205] More specifically, the control unit 236 requests, via the communication unit 231, the portable terminal device 210 to switch to the hands-free mode (step S618).

[0206] The terminal control unit 212 of the portable terminal device 210 receives this request via the terminal communication unit 211, and notifies the hands-free device 230 that the terminal device 210 is going to switch to the hands-free mode (step S620).

[0207] Following this, both the portable terminal device 210 and the hands-free device 230 switch to the hands-free mode (steps S622 and S624).

[0208] The portable terminal device 210 and the hands-free device 230 then perform the hands-free activation operation that activates the microphone 237 and the speaker 238 of the hands-free device 230 to enable the hands-free communication (step S626).

[0209] As has been described, the portable terminal device 210 is first associated with a personal ID of the personal ID device 260 and then registered in the hands-free device 230 as a communication link destination of the hands-free device 230. This allows the hands-free device 230 to specify the registered portable terminal device 210 as its communication target device and establish the communication link with it when the hands-free communication is necessary. That is to say, the hands-free device 230 can select a user from a plurality of users who have the personal ID devices 260.

[0210] With the above examples described based on FIGS. 15 and 19, only one device is registered as a communication link destination in the hands-free device 230, although a plurality of devices may be registered.

[0211] The following describes an example in which three portable terminal devices 210 are registered in the hands-free device 230, and a communication link is established between one of the portable terminal devices 210 and the hands-free device 230.

[0212]FIG. 20 shows a configuration of the hands-free communication system 200 for which three portable terminal devices 210 are registered in the hands-free device 230.

[0213] This hands-free communication system 200 includes the hands-free device 230, three personal ID devices 260, and the three portable terminal devices 210. For the sake of distinction, the three portable terminal devices 210 are called portable terminal devices A210, B210, and C210, and similarly the three personal ID devices 260 are called personal ID devices A260, B260, and C260.

[0214] Each of the personal ID devices A260, B260, and C260 is provided to a different user, and stores a different personal ID. Specifically, the personal ID devices A260, B260, and C260 store personal IDs “1”, “2”, and “3”, respectively.

[0215] The portable terminal devices A210, B210, and C210 also store different MAC addresses and user information in their respective storing units 216.

[0216] FIGS. 21A˜21C are tables showing contents of the storing units 216 of the portable terminal devices A210, B210, and C210.

[0217] As shown in FIG. 21A, the storing unit 216 of the portable terminal device A210 stores the MAC address “0x1234567890AB” and user information “090-1234-5678” that are associated with each other. Similarly, as shown in FIG. 21B, the storing unit 216 of the portable terminal device B210 stores the MAC address “0x234567890ABC” and user information “090-2345-6789” that are associated with each other. As shown in FIG. 21C, the storing unit 216 of the portable terminal device C210 stores the MAC address “0x34567890ABCD” and user information “090-9876-5432” that are associated with each other.

[0218] The portable terminal device A210 and the personal ID device A260 are used by a user A. Similarly, the portable terminal device B210 and the personal ID device B260 are used by another user B, and the portable terminal device C210 and the personal ID device C260 by another user C.

[0219] Here, assume that the user A wishes to register his portable terminal device A210 in the hands-free device 230 as its communication target device. Then the user A performs registration using his personal ID device A260, as shown in FIG. 15.

[0220] This registration produces the personal registration data 232 d, as shown in FIG. 18, which associates the personal ID “1”, the MAC address “0x1234567890AB”, and the user information “090-1234-5678” with one another in the storing unit 232 of the hands-free device 230.

[0221] Here, assume that the user B also wishes to register his portable terminal device B210 in the hands-free device 230 after the user A. Then the user B performs registration using the personal ID device B260, as shown in FIG. 15.

[0222] Consequently, in step S514 of FIG. 15, the display unit 239 displays two sets of user information on the registration screen 239 d as shown in FIG. 22.

[0223]FIG. 22 shows the registration screen 239. Displayed on the first line of the registration screen 239 d are the personal ID “ID1” and the associated user information “090-1234-5678”, which have been earlier registered in the personal registration data 232 d. Also displayed on the second line are the user information “090-2345-6789” of the portable terminal device B210, and the personal ID “ID2” of the personal ID device B260.

[0224] While viewing this registration screen 239 d, the user B operates on the move button 233 a of the operating unit 233 to have the candidate mark 239 m indicate the user information “090-2345-6789”, and presses the “ENTER” button 233 b. As a result, the operating unit 233 outputs the registration signal, so that the control unit 236 associates the personal ID of the personal ID device B260, and the MAC address and the user information of the portable terminal device B210 with one another, and registers them in the personal registration data 232 d in the storing unit 232. This updates the personal registration data 232 d. In this way, the operating unit 233 functions as a means for selecting user information to be registered.

[0225]FIG. 23 is a table showing the updated personal registration data 232 d.

[0226] In this personal registration data 232 d, the personal ID “1” of the personal ID device A260, and the MAC address “0x1234567890AB” and the user information “090-1234-5678” of the portable terminal device A210 are associated with one another. Further, the personal ID “2” of the personal ID device B260, and the MAC address “0x234567890ABC” and the user information “090-2345-6789” of the portable terminal device B210 are associated with one another.

[0227] As a result of such updating of the personal registration data 232 d, the portable terminal devices A210 and B210 are registered in the hands-free device 230 as its communication target devices.

[0228] Here, assume that the user C also wishes to register his portable terminal device C210 in the hands-free device 230 after the users A and B. Then the user C performs registration using the personal ID device C260 as shown in FIG. 15.

[0229] Then in step S514 of FIG. 15, the display unit 239 displays three sets of user information on the registration screen 239 d as shown in FIG. 24.

[0230]FIG. 24 shows the registration screen 239 d. Displayed on the first and second lines on the registration screen 239 d are the already registered personal IDs and associated user information of the portable terminal devices A210 and B210. Also displayed on the third line are the user information “090-9876-5432” of the portable terminal device C210, and the personal ID “ID3” of the personal ID device C260.

[0231] While viewing such registration screen 239 d, the user C operates on the move button 233 a of the operating unit 233 to have the candidate mark 239 m indicate the user information “090-9876-5432”, and presses the “ENTER” button 233 b. As a result, the operating unit 233 outputs the registration signal, so that the control unit 236 associates the personal ID of the personal ID device C260, and the MAC address and the user information of the portable terminal device C210 with one another, and registers them in the personal registration data 232 d in the storing unit 232 to update the personal registration data 232 d.

[0232]FIG. 25 is a table showing the updated personal registration data 232 d.

[0233] In this personal registration data 232 d, the personal ID “1” of the personal ID device A260, and the MAC address “0x1234567890AB” and the user information “090-1234-5678” of the portable terminal device A210 are associated with one another. Further, the personal ID “2” of the personal ID device B260, and the MAC address “0x234567890ABC” and the user information “090-2345-6789” of the portable terminal device B210 are associated with one another. Moreover, the personal ID “3” of the personal ID device C260, and the MAC address “0x34567890ABCD” and the user information “090-9876-5432” of the portable terminal device C210 are associated with one another.

[0234] As a result of such updating of the personal registration data 232 d, the portable terminal devices A210, B210, and C210 are registered in the hands-free device 230 as its communication target devices.

[0235] With reference to FIG. 26, the following sequentially describes operation that ends with the hands-free activation operation performed by one of the registered portable terminal devices A210˜C210 and the hands-free device 230 when the users A, B, and C bring their portable terminal devices A210˜C210 into the automobile.

[0236]FIG. 26 is a sequence diagram showing this operation of the hands-free communication system 200.

[0237] For getting into the automobile, the user A operates on his personal ID device A260, so that it transmits the stored personal ID “1”, and the unlock signal (step S700).

[0238] The control unit 236 of the hands-free device 230 receives this personal ID, recognizes it as currently valid (step S702), and places it into the storing unit 232 (step S704).

[0239] When the user A carrying the portable terminal device A210 gets into the automobile, the portable terminal device A210 enters the communicable range of the hands-free device 230. As a result, the control unit 236 of the hands-free device 230 recognizes the portable terminal device A210 as a device with which it can communicate (step S706).

[0240] Consequently, the hands-free device 230 sends its MAC address to the portable terminal device A210, and the terminal device A210 sends its MAC address and user information to the hands-free device 230 (steps S708 and S710).

[0241] When the user B carrying his personal ID device B260 and the portable terminal device B210 also gets into the automobile, the portable terminal device B210 enters the communicable range of the hands-free device 230. As a result, the control unit 236 of the hands-free device 230 recognizes the portable terminal device B210 as a device with which it can communicate (step S712). Note that the user B does not use his personal ID device B260 here because he is not going to drive the automobile.

[0242] Consequently, the hands-free device 230 sends its MAC address to the portable terminal device B210, and the terminal device B210 sends its MAC address and user information to the hands-free device 230 (steps S714 and S716).

[0243] When the user C carrying his personal ID device C260 and the portable terminal device C210 also gets into the automobile, the portable terminal device C210 enters the communicable range of the hands-free device 230. As a result, the control unit 236 of the hands-free device 230 recognizes the portable terminal device C210 as a device with which it can communicate (step S718). Note that the user C does not use his personal ID device C260 here because he is not going to drive the automobile.

[0244] Consequently, the hands-free device 230 sends its MAC address to the portable terminal device C210, and the terminal device C210 sends its MAC address and user information to the hands-free device 230 (steps S720 and S722).

[0245] Here, assume that the control unit 236 of the hands-free device 230 receives the connect command signal at this point (step S724). Then the control unit 236 searches the personal registration data 232 d in the storing unit 232 for the personal ID “1” that has been recognized in step S704 as currently valid (step S726).

[0246] In the current personal registration data 232 d shown in FIG. 25, three personal IDs of the personal ID devices A260˜C260 and MAC addresses and user information of the three portable terminal devices A210˜C210 are registered. The control unit 236 then finds the valid personal ID “1” in this registration data 232 d, and reads the MAC address “0x1234567890AB” associated with the found personal ID “1”, and specifies, as a communication target device, the portable terminal device A210 that has the read address. The control unit 236 then establishes Bluetooth communication link between the communication unit 231 of the hands-free device 230 and the terminal communication unit 211 of the portable terminal device A210 (step S728).

[0247] When the communication link is established in this way, the hands-free device 230 and the portable terminal device A210 switch to the hands-free mode to enable the hands-free activation operation.

[0248] More specifically, the control unit 236 requests, via the communication unit 231, the portable terminal device A210 to switch to the hands-free mode as in the operation shown in FIG. 19 (step S730).

[0249] The terminal control unit 212 of the portable terminal device A210 receives this request via the terminal communication unit 211, and notifies the hands-free device 230 that the terminal device A210 is going to switch to the hands-free mode (step S732).

[0250] Following this, both the portable terminal device A210 and the hands-free device 230 switch to the hands-free mode (steps S734 and S736).

[0251] The portable terminal device 210 and the hands-free device 230 then perform the hands-free activation operation by activating the microphone 237 and the speaker 238 of the hands-free device 230, so that the hands-free communication can be conducted (step S738).

[0252] For the present embodiment, a plurality of portable terminal devices 210 are registered beforehand in the hands-free device 230 as its communication link destinations, with each terminal device 210 associated with a personal ID of a personal ID device 260. When the user wishes to conduct the hands-free communication, the hands-free device 230 selects one of a plurality of the registered portable terminal devices 210, and establishes the communication link with the selected portable terminal device 210. That is to say, the hands-free device 230 automatically selects, as its communication target, a user operating on a personal ID device 260 out of a plurality of users without requiring the user to perform any troublesome operations. Also with the present hands-free communication system 200, the display unit 239 of the hands-free device 230 displays, for its operator, information regarding users and their portable terminal devices 210 whose addresses are already obtained by the hands-free device 230. The operator can therefore select a desired user out of such users and register an address of a portable terminal device 210 associated with the selected user into the hands-free device 230.

[0253] The following describes operation of a plurality of portable terminal devices 210 and a plurality of hands-free devices 230 when one of the portable terminal devices 210 receives a call. Here, the plurality of portable terminal devices 210 are registered in the plurality of hands-free devices 230 and are within the communicable ranges of all the hands-free devices 230.

[0254]FIG. 27 shows a state of a hands-free communication system 200 in which three portable terminal devices A210, B210, and C210 are within the communicable ranges of the three hands-free devices A230, B230, and C230.

[0255] The portable terminal devices A210˜C210 are registered in the hands-free devices A230˜C230 as their communication target devices in accordance with the registration operation described using FIG. 15.

[0256] That is to say, the storing unit 232 of each of the hands-free devices A230˜C230 stores the personal registration data 232 d that associates three personal IDs with different MAC addresses and user information of the three portable terminal devices A230˜C230 as shown in FIG. 25.

[0257] For ease of explanation, assume that the user A carrying the portable terminal device A210 gets into an automobile, which is equipped with the hands-free device A230, by using the personal ID device A260 and that the user B carrying the portable terminal device B210 gets into an automobile equipped with the hands-free device B230 by using the personal ID device B260, so that the three personal ID devices A260˜C260, the hands-free devices A230˜C230, and the portable terminal devices A210˜C210 are all present within a range in which one device can conduct Bluetooth communication with another.

[0258] When getting into the automobile equipped with the hands-free device A230, the user A operates on the personal ID device A260, which then outputs the personal ID “1”.

[0259] The control unit 236 of the hands-free device A230 recognizes this personal ID “1” as currently valid, and searches the personal registration data 232 d in the storing unit 232 for this personal ID. On finding the personal ID “1”, the control unit 236 associates the aforementioned flag shown as valid (hereafter called a “valid flag”) with the found personal ID “1”, and registers them in the personal registration data 232 d so as to indicate that this personal ID is currently valid.

[0260] The control unit 236 may clear the registered valid flag when a predetermined time passes after the registration, or when the unlock signal outputted by the personal ID device 260 unlocks the car doors. Instead of registering the valid flag, it is possible to store information indicating that the currently valid personal ID is the personal ID “1” in the storing unit 32 as described above.

[0261]FIG. 23A is a table showing the personal registration data 232 d stored in the hands-free device A230 when the user A is in the automobile equipped with the hands-free device A230.

[0262] As shown in the figure, the personal registration data 232 d associates the valid flag, the personal ID “1”, and the MAC address “0x1234567890AB” and user information “090-1234-5678” of the personal terminal device A210 with one another.

[0263] After this, assume that the user B gets into another automobile equipped with the hands-free device B230 by operating on the personal ID device B260 to have the personal ID “2” outputted.

[0264] Then the control unit 236 of the hands-free device B230 recognizes this personal ID “2” as currently valid, and searches the personal registration data 232 d in the storing unit 232 for this personal ID. On finding the personal ID “2”, the control unit 236 associates the valid flag with the found personal ID “2” and registers them in the personal registration data 232 d.

[0265]FIG. 28B is a table showing the personal registration data 232 d stored in the hands-free device B230 when the user B is in the automobile equipped with the hands-free device B230.

[0266] As shown in the figure, the personal registration data 232 d associates the valid flag, the personal ID “2”, and the MAC address “0x234567890ABC” and user information “090-2345-6789” of the personal terminal device B210 with one another.

[0267] On the other hand, nobody is going to get into the automobile equipped with the hands-free device C230. As a result, personal registration data 232 d stored in the storing unit 232 of the hands-free device C230 only stores data that has been registered earlier.

[0268]FIG. 28C is a table showing this personal registration data 232 d stored in the hands-free device C230. This personal registration data 232 d indicates that no valid flag is registered, and therefore none of the personal IDs are currently valid.

[0269] After this, in a similar way to steps S706˜S722 shown in FIG. 26, the hands-free devices A230˜C230 send their MAC addresses to the portable terminal devices A210˜C210, while the portable terminal devices A210˜C210 also send their MAC addresses and user information to the hands-free devices A230˜C230. Consequently each of the hands-free devices A230˜C230 and the portable terminal devices A210˜C210 has a plurality of MAC addresses of communication target devices.

[0270] When the connect command signal is inputted to the control unit 236 of any of the hands-free devices A230˜C230 at this point as shown in step S724 in FIG. 26, the hands-free device 230 receiving the connect command signal searches its personal registration data 232 d for a valid personal ID indicated by the valid flag, and establishes a communication link with a portable terminal device 210 associated with the valid personal ID in the similar way to that shown in FIG. 26.

[0271] On the other hand, when one of the portable terminal devices A210-C210, e.g., the terminal device A210 receives a call before one of the hands-free devices 230A˜230C receives the connect command signal, the portable terminal device A210 performs the following operation to establish a communication link with the hands-free device A230 alone that is present in the same automobile as the portable terminal device A210.

[0272] More specifically, on receiving the call, the terminal control unit 212 of the portable terminal device A210 detects that the three hands-free devices A230˜C230 exist in a communicable range of the portable terminal device A210, and sends a connect request signal requesting each hands-free device 230 to establish a communication link with the portable terminal device A210.

[0273] Each hands-free device 230 then judges from the sent connect request signal whether the MAC address of the requesting portable terminal device A210 is registered in the personal registration data 232 d in the storing unit 232 and associated with a currently valid personal ID indicated by the valid flag.

[0274] More specifically, the control unit 236 of the hands-free device A230 searches the personal registration data 232 d in the storing unit 232 shown in FIG. 28A for the MAC address of the requesting portable terminal device A210, and judges whether this MAC address is associated with the valid flag. Similarly, the control units 236 of the hands-free devices B230 and C230 search the personal registration data 232 d shown in FIGS. 28B and 28C, respectively, for the MAC address of the requesting portable terminal device A210, and judge whether this MAC address is associated with the valid flag.

[0275] Consequently, the control unit 236 of the hands-free device A230 judges from the valid flag that the MAC address of the portable terminal device A210 is associated with the currently valid personal ID, and sends a connect response signal to the connect request signal.

[0276] As a result, the portable terminal device A210 that has received a call can establish a communication link with the hands-free device A230 alone in the same automobile even when other hands-free devices B230 and C230 exist within the communicable range of the portable terminal device A210. The portable terminal device A210 may send the above connect request signal to the hands-free device A230 alone that stores the MAC address of portable terminal device A210 associated with the valid personal ID, although the above embodiment describes the portable terminal device A210 sending this connect request signal to all the hands-free devices A230˜C230.

[0277] In more detail, before sending the connect request signal, the portable terminal device A210 may send, to all the hands-free devices A230˜C230, an inquiry signal to make an inquiry about a registered MAC address associated with a currently valid personal ID. In response to this inquiry signal, each hands-free device 230 sends MAC addresses to the portable terminal device A210, which then compares each sent MAC address with its own MAC address. On finding that the MAC address sent from the hands-free device A230 matches with its own MAC address, the portable terminal device A210 sends the connect request signal to this hands-free device A230 alone.

[0278] In the above embodiment, it is only the hands-free device 230 that stores the personal registration data 232 d. The communication link is then established between the hands-free device 230 and the portable terminal device 210 associated with the valid personal ID of the personal ID device 260. It is alternatively possible, however, for the portable terminal device 210 to perform such function of the hands-free device 230.

[0279]FIG. 29 shows the construction of the hands-free communication system 200 that includes such portable terminal device 210 having the above function of the hands-free device 210.

[0280] This hands-free communication system 200 also includes the personal ID device 270 that outputs a personal ID like the personal ID device 260. The terminal control unit 212 of the portable terminal device 210 receives the personal ID from the personal ID device 270, and associates the received personal ID with an MAC address sent from the hands-free device 230 and stores them in the storing unit 216.

[0281] This enables the portable terminal device 210 to automatically select a hands-free device 230 associated with the personal ID sent from the personal ID device 270 out of a plurality of hands-free devices 230 within a communicable range to establish a communication link to the selected hands-free device 230. The personal ID device 260/270 may be a fingerprint authentication device that outputs fingerprint information of the user as the personal ID, or may be a password input device that stores a password in advance and outputs it as the personal ID.

[0282] With the present embodiment, a personal ID, an MAC address, user information, and a valid flag are registered in the personal registration data 232 d in the storing unit 232 of the hands-free device 230. In addition to such information, it is also possible to register a priority in the personal registration data 232 d assigned to a communication target device that has an MAC address and user information.

[0283] The hands-free device 230 selects a communication target device to which the highest priority is assigned in the personal registration data 232 d. Each priority is registered, for instance, by user operation on the operating unit 233 of the hands-free device 230.

[0284]FIG. 30 is an example table showing the personal registration data 232 d that contains such priorities.

[0285] This personal registration data 232 d associates the following sets of data with one another: the personal ID “1”; the MAC address “0x1234567890AB” and the user information “090-1234-5678” of the portable terminal device A210; a valid flag; and a priority “1”, which is the highest. The personal registration data 232 d also associates the following sets of data with one another: the personal ID “2”; the MAC address “0x234567890ABC” and the user information “090-2345-6789” of the portable terminal device B210; and a priority “2”, which is the second highest. Moreover, the personal ID “3”, the MAC address “0x34567890ABCD” and the user information “090-9876-5432” of the portable terminal device C210, and the priority “3”, which is the lowest, are associated with one another.

[0286] When selecting one of the portable terminal devices A210˜C210, the control unit 236 of the hands-free device 230 refers to the above personal registration data 232 d, and tries to establish a communication link to the portable terminal device A210 indicated by the valid flag. When this is not possible, however, for such reason that the portable terminal device A210 does not exist within the communicable range, the control unit 236 specifies the portable terminal device B210 associated with the second-highest priority, and tries to establish a communication link to the specified portable terminal device B210. However, when the portable terminal device B210 also does not exist within the communicable range, the control unit 236 tries to establish a communication link with the portable terminal device C210 associated with the next highest priority.

[0287] By registering such priorities in the personal registration data 232 d in advance, the hands-free device 230 can select one of a plurality of portable terminal devices 210 in accordance with the registered priorities to establish a communication link even when a portable terminal device 210 indicated by the valid flag does not exist in the communicable range of the hands-free device 230.

[0288] When priorities are registered in the personal registration data 232 d in this way, a plurality of valid flags may be also registered in this personal registration data 232 d. In this case, the control unit 236 of the hands-free device 230 selects, from portable terminal devices 210 indicated by the valid flags, a portable terminal device 210 to which the highest priority is assigned to establish a communication link with the selected portable terminal device 210.

[0289] When priorities are registered in the personal registration data 232 d in the stated way, it is also possible to associate a single personal ID with a plurality of MAC addresses and user information of a plurality of portable terminal devices 210 in the personal registration data 232 d. In this case, the control unit 236 of the hands-free device 230 selects a portable terminal device 210, to which the highest priority is assigned, from the plurality of portable terminal devices 210 associated with the same personal ID to establish a communication link with the selected portable terminal device 210.

[0290] In this way, the control unit 236 selects a portable terminal device 210 in accordance with priorities, personal IDs, and valid flags.

[0291] When the priorities are registered in the personal registration data 232 d as described above, it is not necessary to register a personal ID in the personal registration data 232 d. In this case, the control unit 236 of the hands-free device 230 selects a portable terminal device 210 that has an MAC address associated with the highest priority as a communication target device. This still allows the hands-free device 230 to specify a communication target device to establish a communication link without requiring the user to perform troublesome operations.

[0292] Third Embodiment

[0293] A hands-free communication system 200 of the present embodiment has the same basic construction as the hands-free communication system 200 of the second embodiment. Accordingly, elements common to both the hands-free communication systems 200 are given the same reference numbers and not described below. The following only describes elements characteristic to the present embodiment in detail.

[0294]FIG. 31 is a block diagram showing the hands-free communication system 200 of the present embodiment.

[0295] A storing unit 232 of a hands-free device 230 of the present embodiment is achieved by a Secure Digital (SD) (a trademark of Toshiba Corporation) Memory Card, for instance, and is detachable from the hands-free device 230.

[0296] This storing unit 232 is inserted into a card reader internal or external to a personal computer (PC), for example. The PC writes information, which the PC generates or obtains from another device, onto the inserted storing unit 232 via the card reader. The PC also reads information from the storing unit 232, edits the read information, and writes the edited information into the storing unit 232.

[0297] That is to say, unlike the hands-free device 230 of the second embodiment, the hands-free device 230 of the present embodiment does not have the operating unit 233 and the display unit 239. The registration as shown in FIG. 15 is therefore performed by another device such as a PC.

[0298] More specifically, the user produces personal registration data 232 d as shown in FIG. 25, FIG. 28, or FIG. 30 by using the PC, and inserts the storing unit 232 into the card reader of the PC to write the produced personal registration data 232 d into the storing unit 232. The user then connects the storing unit 232 to the hands-free device 230.

[0299] By having a device such as a PC edit the personal registration data 232 d in the storing unit 232 in this way, the operating unit 233 and the display unit 239 become unnecessary within the hands-free device 230. This downsizes the hands-free device 230 and also reduces the cost of the hands-free communication system 200.

[0300] The above storing unit 232 may be fixed on the hands-free device 230, although the above embodiment describes the storing unit 232 as detachable from the hands-free device 230. In such case, the control unit 236 of the hands-free device 230 is connected to a PC, for instance, with a cable or wirelessly, and transfers data to/from the PC. The control unit 236 then writes the personal registration data 232 d transferred from the PC into the storing unit 232. This hands-free device 230 also does not require the operating unit 233 and the display unit 239, and therefore downsizing of the hands-free device 230 and cost reduction of the hands-free communication system 200 can be achieved.

[0301] Fourth Embodiment

[0302] A hands-free communication system 200 of the fourth embodiment has the same basic construction as the hands-free communication system 200 of the third embodiment. Therefore elements common to both the communication systems 200 are given the same reference numbers and not described below. The following only describes elements characteristic to the present embodiment in detail.

[0303]FIG. 32 is a block diagram showing the hands-free communication system 200 of the present embodiment.

[0304] A control unit 236 of a hands-free device 230 of the present embodiment receives a signal containing an MAC address and user information via a communication unit 231 from a portable terminal device 210. Based on this signal, the control unit 236 measures electric field intensity of a wireless signal sent from the portable terminal device 210, associates the measured electric field intensity with the received MAC address and user information, and places them into the storing unit 232.

[0305] When the storing unit 232 only stores one MAC address and a single set of user information, the hands-free device 230 specifies, as its communication target device, a portable terminal device 210 that has the stored MAC address and user information so as to establish a communication link. When the storing unit 232 stores a plurality of MAC addresses and a plurality sets of user information, the hands-free device 230 specifies, as its target communication device, a portable terminal device 210 that has an MAC address and user information associated with the highest electric field intensity to establish a communication link.

[0306] With reference to FIGS. 33 and 34, the following describes operation performed when the hands-free device 230 selects one of three portable terminal devices A210, B210, and C210 present within the communicable range of hands-free device 230, and establishes a communication link with the selected portable terminal device 210.

[0307]FIG. 33 shows a configuration of the hands-free communication system 200 including the three portable terminal devices A210˜C210 within the communicable range of the hands-free device 230.

[0308]FIG. 34 is a sequence diagram showing this operation of the hands-free communication system 200.

[0309] The following description is provided on the assumption that a user A carrying the portable terminal device A210 gets into an automobile equipped with the hands-free device 230 and takes the driver seat, and users B and C carrying the portable terminal devices B210 and C210, respectively, get into the same automobile as passengers.

[0310] When the user A carrying the portable terminal device A210 gets into the automobile, the terminal device A210 enters the communicable range of the hands-free device 230. As a result, the control unit 236 of the hands-free device 230, which is searching for a communicable device, recognizes the portable terminal device A210 as the communicable device (step S800).

[0311] Consequently, the terminal device A210 sends its MAC address and user information to the hands-free device 230, and the hands-free device 230 sends its MAC address to the portable terminal device A210. In this way, the hands-free device 230 obtains the MAC address and user information of the portable terminal device A210 (step S802), while the portable terminal device A210 obtains the MAC address of the hands-free device 230 (step S804).

[0312] Following this, the control unit 236 of the hands-free device 230 measures electric field intensity of a wireless signal from the portable terminal device A210 by referring to a signal sent containing the MAC address and user information. The control unit 236 then associates the measured electric field intensity with the MAC address and user information, and places them into the storing unit 232 (step S806).

[0313] When the user B carrying the portable terminal device B210 also gets into the same automobile, the portable terminal device B210 enters the communicable range of the hands-free device 230. As a result, the control unit 236 of the hands-free device 230 searching for a communicable device recognizes the portable terminal device B210 as the communicable device (step S808).

[0314] Consequently, the hands-free device 230 sends its MAC address to the portable terminal device B210, and the terminal device B210 sends its MAC address and user information to the hands-free device 230. In this way, the hands-free device 230 obtains the MAC address and user information of the portable terminal device B210 (step S810), while the portable terminal device B210 obtains the MAC address of the hands-free device 230 (step S812).

[0315] Following this, the control unit 236 of the hands-free device 230 measures electric field intensity of a wireless signal from the portable terminal device B210 by referring to a signal sent containing the MAC address and user information. The control unit 236 then associates the measured electric field intensity with the MAC address and user information, and places them into the storing unit 232 (step S814).

[0316] After this, when the user C carrying the portable terminal device C210 also gets into the same automobile, the portable terminal device C210 also enters the communicable range of the hands-free device 230. As a result, the control unit 236 of the hands-free device 230 searching for a communicable device recognizes the portable terminal device C210 as a communicable device (step S816).

[0317] Consequently, the hands-free device 230 sends its MAC address to the portable terminal device C210, and the terminal device C210 sends its MAC address and user information to the hands-free device 230. In this way, the hands-free device 230 obtains the MAC address and user information of the portable terminal device C210 (step S818), while the portable terminal device C210 obtains the MAC address of the hands-free device 230 (step S820).

[0318] Following this, the control unit 236 of the hands-free device 230 measures electric field intensity of a wireless signal from the portable terminal device C210 by referring to a signal sent containing the MAC address and user information. The control unit 236 then associates the measured electric field intensity with the MAC address and user information, and places them into the storing unit 232 (step S822).

[0319]FIG. 35 is a table showing field intensity data 232 e that is generated and stored in the storing unit 232 as described above.

[0320] In this field intensity data 232 e, the MAC address “0x1234567890AB” and the user information “090-1234-5678” of the portable terminal device A210 are associated with “E1” which indicates the electric field intensity of the wireless signal of the portable terminal device A210. Further, the MAC address “0x234567890ABC” and the user information “090-2345-6789” of the portable terminal device B210 are associated with “E2” which indicates the electric field intensity of the wireless signal of the portable terminal device B210. Moreover, the MAC address “0x34567890ABCD” and the user information “090-9876-5432” of the portable terminal device C210 are associated with “E3” which indicates the electric field intensity of the wireless signal of the portable terminal device C210.

[0321] In the automobile, the user A takes the driver seat, and the users B and C take backseats. This places the portable terminal device A210 of the user A nearest the hands-free device 230, the terminal device B210 of the user B second nearest, and the terminal device C210 farthest from the hands-free device 230.

[0322] That is to say, the three electric field intensities “E1”, “E2”, and “E3” in the field intensity data 232 e satisfies an expression “E1>E2>E3.”

[0323] Here, assume that a connect command signal to establish a communication link is inputted to the control unit 236 of the hands-free device 230 as a result of operation by the user A (step S824). The control unit 236 then searches the field intensity data 232 e for the highest field intensity (step S826).

[0324] As a result, the control unit 236 finds the highest electric field intensity “E1” in the field intensity data 232 e, and reads the MAC address “0x1234567890AB” associated with the highest electric intensity “E1”. The control unit 236 specifies, as its communication target device, the portable terminal device A210 that has the read MAC address, and establishes Bluetooth communication link between a communication unit 231 of the hands-free device 230 and a terminal communication unit 211 of the specified portable terminal device A210 (step S828).

[0325] After the communication link is established in this way, the hands-free device 230 and the portable terminal device A210 switch to the hands-free mode and conducts the hands-free activation operation as shown in steps S730˜S738 in FIG. 26.

[0326] With the hands-free communication system 200 of the present embodiment, it is unnecessary to register beforehand a personal ID, and an MAC address and user information of a portable terminal device 210 into the storing unit 232 of the hands-free device 230 as required in the second and third embodiments. Without such prior registration, the present hands-free device 230 can automatically specify an appropriate portable terminal device 210 as a communication target device in accordance with electric field intensity, and establish a communication link with the specified portable terminal device 210. In addition, as the present hands-free communication system 200 does not require a personal ID device 260, the cost reduction can be achieved. Moreover, the present hands-free device 230 specifies, as its communication target device, a portable terminal device 210 that sends a signal of the highest electric field intensity. Consequently, there is a high probability of the hands-free device 230 selecting a portable terminal device 210 of a driver, who is nearest the hands-free device 230, which enables the hands-free device 230 to select the most suitable target user.

[0327] In the above embodiment, an MAC address and user information of a portable terminal device 210 are not registered beforehand in the hands-free device 230. However, they may be registered in advance as in the second and third embodiments. In this case, the field intensity data 232 e shown in FIG. 35, for instance, that excludes the electric field intensities registered beforehand in the storing unit 232 of the hands-free device 230. In steps S806, S814, and S822 in FIG. 34, each measured electric field intensity is associated with an MAC address and user information registered beforehand, and placed into the storing unit 232.

[0328] The first to fourth embodiments have been used to describe the hands-free communication system of the present invention, although it should be clear that the present invention is not limited to these embodiments. Possible modifications are described below.

[0329] The first to fourth embodiments describe a hands-free communication system as an example of a communication system according to the present invention, although a communication system of the present invention is not limited to such hands-free communication system.

[0330] In the first to fourth embodiments, the hands-free device 130/230 is installed in an automobile although they may be installed in other places, such as a vehicle other than an automobile, and a building. The hands-free device 130/230 does not have to be fixed in one place and may be portable.

[0331] In the first to fourth embodiments, Bluetooth wireless communication is performed between the hands-free device 130/230 and the portable terminal device 110/210. However, such wireless communication is not limited to Bluetooth communication, and other wireless communication complying with other standards may be alternatively performed. Instead of an MAC address, other address that is unique to a device, such as a telephone number, may be used.

[0332] In the first to fourth embodiments, the hands-free device 130/230 first obtains an MAC address of the portable terminal device 110/210, and then the portable terminal device 110/210 obtains an MAC address of the hands-free device 130/230. It is alternatively possible, however, that the portable terminal device 110/210 first obtains an MAC address of the hands-free device 130/230.

[0333] The hands-free device 130/230 may search a device with which it can conduct Bluetooth communication only when receiving a user operation, although the first to fourth embodiments describe the hands-free device 130/230 performing this search all the time. It is alternatively possible for the portable terminal device 110/210 to perform this search and request the hands-free device 130/230 found through the search to send its MAC address. The portable terminal device 110/210 may send its MAC address and user information at the same time or different times. When Bluetooth communication is performed, it is possible to include user information in a response (“LMP_NAME_RES”) to an inquiry (“LMP_NAME_REQ”) about user-friendly names, which is sent from the hands-free device 130/230 to the portable terminal device 110/210.

[0334] In the first to fourth embodiments, the hands-free device 130/230 selects one of a plurality of portable terminal devices 130/230 within the communicable range. However, the hands-free device 130/230 may be connected to a plurality of portable terminal devices 110/210. This connection may be in a star topology or a bus topology.

[0335] While communicating with a portable terminal device 110/210 which has been selected out of a plurality of terminal devices 110/210, the hands-free device 130/230 may change a communication target device from the current portable terminal device 110/210 to another portable terminal device 110/210. For instance, when the portable terminal device B210 receives an emergency call while the hands-free device 230 communicates with the portable terminal device A210, the terminal device B210 makes a special request to the hands-free device 230 for establishment of a communication link to the terminal device B210. On receiving this request, the hands-free device 230 clears a communication link with the portable terminal device A210, and establishes a new communication link with the requesting portable terminal device B210. This can increase ease of use of the present hands-free communication system.

[0336] It is also possible for the hands-free device 130/230 and the portable terminal device 110/210 of the first to fourth embodiments to authenticate each other before establishing a communication link. This can be performed, for instance, by providing passwords to both the hands-free device 130/230 and the portable terminal device 110/210 and having the user input the password. This authentication can prevent the hands-free device 130/230 from establishing a communication link with an unauthorized portable terminal device 110/210.

[0337] The first to fourth embodiments describe the user information as a telephone number, although it is not limited to a telephone number and may be a model number (such as “P504-i”) or a serial number of the portable terminal device 110/210, or user-friendly text information, such as “Matsushita's Telephone Number”.

[0338] In the first to fourth embodiments, the hands-free device 130/230 stores its own MAC address in the storing unit 132/232, and the portable terminal device 110/210 stores its own MAC address in the storing unit 116/216. However, such MAC address may be stored in regions other than the storing units 132/232 and 116/216, such as the communication unit 131/231 and the terminal communication unit 111/211.

[0339] The first and second embodiments describe the hands-free device 130/230 as including the microphone 137/237, the speaker 138/238, and the display unit 139/239. However, it is not necessary for the hands-free device 130/230 to include all of such units. Similarly, the portable terminal device 110/210 is described in the first and second embodiments as including the microphone 113/213, the speaker 114/214, and the display unit 115/215, although the portable terminal device 110/210 does not have to include all of these units. When the hands-free device 130/230 does not include the display unit 139/239, the control unit 136/236 of the hands-free device 130/230 may include a voice synthesizing unit that generates guide voice for notifying the user of the user information, which is displayed by the display unit 139/239 in the above embodiments. The generated guide voice is outputted by the speaker 138/238.

[0340] As in the first embodiment, the connect command signal may be outputted when car doors are unlocked by the unlock signal sent from a transmitter of a keyless entry system, or when the engine is started, or when the driver's taking the seat is detected for the second and third embodiments also. This allows the hands-free device 230 to specify an appropriate portable terminal device 210 and switch to the hands-free mode, without the user operating on the hands-free device 230 and noticing switching to the hands-free mode.

[0341] In the second embodiment, the control unit 235 of the hands-free device 230 measures electric field intensity of a signal sent from a portable terminal device 210, but it does not store the measured field intensity into the storing unit 232. However, the control unit 236 may register the measured electric field intensity in the personal registration data 232 d in the storing unit 232 as in the fourth embodiment. This enables the control unit 236 to select an appropriate portable terminal device 210 in a more precise manner in accordance with the priority, the personal ID, the valid flag, and the electric field intensity. 

What is claimed is:
 1. A communication system that comprises a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, wherein one of the plurality of communication devices includes: an obtaining unit operable to obtain an address of another communication device from the another communication device; a registering unit operable to register one of addresses obtained by the obtaining unit into the registering unit in response to a reception of a first trigger signal; and a specifying unit operable to read the registered address from the registering unit and specify a communication device as a target communication device in response to a reception of a second trigger signal, the specified communication device having the read registered address.
 2. The communication system of claim 1 with which a user performs hands-free communication, wherein the one of the plurality of communication devices is installed in an automobile, and the another communication device has a function of a portable telephone.
 3. The communication system of claim 2, wherein the second trigger signal indicates that an engine of the automobile is started.
 4. The communication system of claim 2, wherein a transmitter is provided to the automobile, the transmitter transmitting an unlock signal to unlock a door of the automobile in response to an operation by the user, and the second trigger signal indicates that the door is unlocked by the unlock signal.
 5. The communication system of claim 2, wherein the automobile includes a seating detecting unit operable to detect seating of a driver of the automobile, and the second trigger signal indicates that the seating is detected.
 6. The communication system of claim 1, wherein the first trigger signal is outputted as a result of an operation by a user.
 7. The communication system of claim 1, wherein the one of the plurality of communication devices also includes a selecting unit operable to select one of addresses obtained by the obtaining unit, and the registering unit registers the selected address into the registering unit.
 8. The communication system of claim 7, wherein the obtaining unit also obtains user information from the another communication device, the user information indicating information regarding a user of the another communication device, and the one of the plurality of devices also includes a display unit operable to display the obtained user information.
 9. The communication system of claim 1, wherein the one of the plurality of communication devices performs wireless communication with the another communication device, and the obtaining unit obtains the address of the another communication device by performing wireless communication with the another communication device.
 10. The communication system of claim 9, wherein the one of the plurality of communication devices also includes a measuring unit operable to measure an electric field intensity of a wireless signal sent from the another communication device, and the address registered by the registering unit is sent via a wireless signal, which is specified as having a highest electric field intensity as a result of measurement by the measuring unit.
 11. The communication system of claim 1, wherein the one of the plurality of devices also includes a storing unit operable to associate the address obtained by the obtaining unit with a priority and store the address associated with the priority, and the address registered by the registering unit is associated with a highest priority of all priorities stored in the storing unit.
 12. A communication device that communicates with a communication apparatus by obtaining an address of the communication apparatus, the communication device comprising: an obtaining unit operable to obtain an address of a communication apparatus from the communication apparatus; a registering unit operable to register one of addresses obtained by the obtaining unit into the registering unit in response to a reception of a first trigger signal; and a specifying unit operable to read the registered address from the registering unit and specify a communication apparatus as a target communication apparatus in response to a reception of a second trigger signal, the specified communication apparatus having the read registered address.
 13. The communication device of claim 12 that is installed in an automobile and communicates with a portable phone brought in the automobile to allow a user to perform hands-free communication.
 14. The communication device of claim 13, wherein the second trigger signal indicates that an engine of the automobile is started.
 15. The communication device of claim 13, wherein a transmitter is provided to the automobile, the transmitter transmitting an unlock signal to unlock a door of the automobile in response to an operation by the user, and the second trigger signal indicates that the door is unlocked by the unlock signal.
 16. The communication device of claim 13, wherein the automobile includes a seating detecting unit operable to detect seating of a driver of the automobile, and the second trigger signal indicates that the seating is detected.
 17. The communication device of claim 12, wherein the first trigger signal is outputted as a result of an operation by a user.
 18. A communication system that comprises a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, wherein one of the plurality of communication devices includes: an obtaining unit operable to obtain a set of identification (ID) information assigned to a user, and an address of another communication device from the another communication device; a registering unit operable to associate an obtained address with a latest set of ID information that is most recently obtained by the obtaining unit, and register the obtained address and the latest set of ID information into the registering unit; and a specifying unit operable to search the registering unit for the latest set of ID information and specify a communication device as a target communication device, the specified communication device having the address associated with the latest set of ID information.
 19. The communication system of claim 18, wherein the one of the plurality of communication devices also includes a selecting unit operable to select, in accordance with an operation by a user, one of addresses obtained by the obtaining unit, and the registering unit registers the selected address into the registering unit.
 20. The communication system of claim 19, wherein the obtaining unit also obtains user information from the another communication device, the user information indicating information regarding a user of the another communication device, and the one of the plurality of communication devices also includes a display unit operable to display the obtained user information.
 21. The communication system of claim 18, wherein the one of the plurality of communication devices performs wireless communication with the another communication device, and the obtaining unit obtains the address of the another communication device by performing wireless communication with the another communication device.
 22. The communication system claim 21, wherein the one of the plurality of communication devices also includes a measuring unit operable to measure an electric field intensity of a wireless signal sent from the another communication device, the registering unit also associates the obtained address with the measured electric field intensity and also registers the electric field intensity associated with the address into the registering unit, and the specifying unit specifies, when finding no latest set of ID information after the search through the registering unit, a communication device as a target communication device, the specified communication device having an address associated with the highest electric field intensity of all electric field intensities registered in the registering unit.
 23. The communication system claim 18, wherein the registering unit also associates the obtained address with a priority and registers the address associated with the priority into the registering unit, and the specifying unit specifies, when finding no latest set of ID information after the search through the registering unit, a communication device as a target communication device, the specified communication device having an address associated with a highest priority of all priorities registered in the registering unit.
 24. The communication system of claim 18 with which a user performs hands-free communication, wherein the one of the plurality of communication devices is installed in an automobile, and the another communication device has a function of a portable telephone.
 25. The communication system of claim 24, wherein as soon as an engine of the automobile is started, the specifying unit specifies the communication device.
 26. The communication system of claim 24, wherein a transmitter is provided to the automobile, the transmitter transmitting an unlock signal to unlock a door of the automobile in response to an operation by the user, and the specifying unit specifies the communication device as soon as the door is unlocked.
 27. The communication system of claim 24, wherein the automobile includes a seating detecting unit operable to detect seating of a driver of the auto mobile, and the specifying unit specifies the communication device as soon as the seating is detected.
 28. A communication device that communicates with a communication apparatus by obtaining an address of the communication apparatus, the communication device comprising: an obtaining unit operable to obtain a set of ID information assigned to a user, and an address of a communication apparatus from the communication apparatus; a registering unit operable to associate an obtained address with a latest set of ID information that is most recently obtained by the obtaining unit, and register the obtained address and the latest set of ID information into the registering unit; and a specifying unit operable to search the registering unit for the latest set of ID information and specify a communication apparatus as a target communication apparatus, the specified communication apparatus having the address associated with the latest set of ID information.
 29. A communication device that communicates with a communication apparatus by obtaining an address of the communication apparatus, the communication device comprising: an obtaining unit operable to obtain, from a communication apparatus, a set of ID information assigned to a user, an address of the communication apparatus, and user information indicating information regarding a user of the communication apparatus; a display unit operable to display the obtained user information; a selecting unit operable to select, in accordance with an operation by a user, one of addresses obtained by the obtaining unit; a registering unit operable to associate the selected address with a latest set of ID information that is most recently obtained by the obtaining unit, and register the selected address and the latest set of ID information into the registering unit; and a specifying unit operable to search the registering unit for the latest set of ID information and specify a communication apparatus as a target communication apparatus, the specified communication apparatus having the address associated with the latest set of ID information.
 30. A communication system that comprises a plurality of communication devices, each of which performs wireless communication with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, wherein one of the plurality of communication devices includes: an obtaining unit operable to obtain an address of another communication device from the another communication device through wireless communication; a measuring unit operable to measure an electric field intensity of a wireless signal sent from the another communication device; a registering unit operable to associate the obtained address with an electric field intensity that is measured by the measuring unit when the address is obtained, and to register the address and the electric field intensity associated with each other into the registering unit; and a specifying unit operable to search the registering unit for a highest electric field intensity and specify a communication device as a target communication device, the specified communication device having an address associated with the highest electric field.
 31. A communication device that communicates with a communication apparatus by obtaining an address of the communication apparatus, the communication device comprising: an obtaining unit operable to obtain an address of a communication apparatus from the communication apparatus through wireless communication; a measuring unit operable to measure an electric field intensity of a wireless signal sent from the communication apparatus; a registering unit operable to associate the obtained address with an electric field intensity that is measured by the measuring unit when the address is obtained, and to register the address and the electric field intensity associated with each other into the registering unit; and a specifying unit operable to search the registering unit for a highest electric field intensity and specify a communication apparatus as a target communication apparatus, the specified communication apparatus having an address associated with the highest electric field.
 32. A communication system that comprises a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, wherein one of the plurality of communication devices includes: an obtaining unit operable to obtain an address of another communication device from the another communication device; a registering unit operable to associate the obtained address with a priority and register the address associated with the priority into the registering unit; and a specifying unit operable to specify a communication device as a target communication device, the specified communication device having an address associated with a highest priority of all priorities registered in the registering unit.
 33. A communication device that communicates with a communication apparatus by obtaining an address of the communication apparatus, the communication device comprising: an obtaining unit operable to obtain an address of a communication apparatus from the communication apparatus; a registering unit operable to associate the obtained address with a priority and register the address associated with the priority into the registering unit; and a specifying unit operable to specify a communication apparatus as a target communication apparatus, the specified communication apparatus having an address associated with a highest priority of all priorities registered in the registering unit.
 34. A communication method used for a communication device included in a communication system, which comprises a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, the communication method including: an obtaining step for obtaining an address of another communication device from the another communication device; a registering step for registering one of addresses that is obtained in the obtaining step into a storage region in response to a reception of a first trigger signal; and a specifying step for reading the registered address from the storage region and specifying a communication device as a target communication device in response to a reception of a second trigger signal, the specified communication device having the read registered address.
 35. A communication method used for a communication device included in a communication system, which comprises a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, the communication method including: an obtaining step for obtaining a set of ID information assigned to a user, and an address of another communication device from the another communication device; a registering step for associating an obtained address with a latest set of ID information that is most recently obtained in the obtaining step, and registering the obtained address and the latest set of ID information; and a specifying step for searching all registered sets of ID information for the latest set of ID information and specifying a communication device as a target communication device, the specified communication device having the address associated with the latest set of ID information.
 36. A communication method used for a communication device included in a communication system, which comprises a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, the communication method including: an obtaining step for obtaining an address of another communication device from the another communication device through wireless communication; a measuring step for measuring an electric field intensity of a wireless signal sent from the another communication device; a registering step for associating the obtained address with an electric field intensity that is measured in the measuring step when the address is obtained, and for registering the address and the electric field intensity associated with each other; and a specifying step for searching all registered electric field intensities for a highest electric field intensity and specifying a communication device as a target communication device, the specified communication device having an address associated with the highest electric field.
 37. A program for a communication device included in a communication system, which comprises a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, the program including: an obtaining step for obtaining an address of another communication device from the another communication device; a registering step for registering one of addresses that is obtained in the obtaining step into a storage region in response to a reception of a first trigger signal; and a specifying step for reading the registered address from the storage region and specifying a communication device as a target communication device in response to a reception of a second trigger signal, the specified communication device having the read registered address.
 38. A program for a communication device included in a communication system, which comprises a plurality of communication devices, each of which communicates with another communication device out of the plurality of communication devices by obtaining an address of the another communication device, a different address being assigned to each communication device, the program including: an obtaining step for obtaining a set of ID information assigned to a user, and an address of another communication device from the another communication device; a registering step for associating an obtained address with a latest set of ID information that is most recently obtained in the obtaining step, and registering the obtained address and the latest set of ID information; and a specifying step for searching all registered sets of ID information for the latest set of ID information and specifying a communication device as a target communication device, the specified communication device having the address associated with the latest set of ID information. 